1. Field of the Invention
The present invention relates to a medical targeting apparatus of the type having an assembly composed of several parts arranged so as to be able to be displaced relative to one another, an instrument control unit connected to the assembly, adjustment means for moving the parts and the instrument control unit relative to one another, a patient mount for positioning at least a body part of a patient in a diagnostic imaging apparatus, and a marking means, connected with the patient mount in a first position, for the production of a visible mark in an image of the body part.
2. Description of the Prior Art
In minimally invasive interventions in which the target region cannot be observed directly, the use of imaging methods such as e.g. ultrasound, X-rays or magnetic resonance allows a high degree of precision to be achieved in the positioning of a corresponding instrument. The progress of the intervention is, for example, made visible continuously. The planning of an optimal access path of the instrument to the target area also can take place using previously produced images. If necessary, a natural or artificial fixed point in the area under examination can be used as a reference point.
European Application 0 752 237 discloses a mounting means for a surgical instrument is known. The mounting means has several arms that are pivotably connected with one another via joints. The entire mounting means is connected in displaceable fashion to a patient positioning means by a rail system. However, this mounting means is not provided or suitable for surgical interventions with monitoring of diagnostic tomograms.
In U.S. Pat. No. 4,629,989, a diagnostic magnetic resonance apparatus with a laser marking apparatus is described. The laser marking apparatus serves for precisely positioning an area of examination in the imaging area of the magnetic resonance apparatus.
A medical targeting apparatus of the type initially described is known from U.S. Pat. No. 5,056,523. This known targeting apparatus is provided for positioning the tip of a probe relative to a target region in a protruding body part of a patient, such as for example a female breast, with X-ray monitoring. The body part to be examined is fixed between two plates that are parallel and are transparent to radiation. One of the plates has a number of through-holes for the probe. In addition, marks that are visible in a transillumination image are present on this plate as a localization aid. Using the transillumination images, a probe guide is positioned in such a way that the probe can be guided immediately on a path to the target region. An additional scale, that is arranged coplanar to the instrument control unit and that is shown on a transillumination image, makes it possible to determine the depth of penetration.
From U.S. Pat. No. 5,678,549, a stereotactic auxiliary unit for a nuclear magnetic resonance tomography apparatus spin tomograms is known that permits a localization in a female breast of data that are visible in a magnetic resonance tomogram. The breast is thereby fixed and compressed with two compression plates. At least one of the compression plates has bored guide holes, via which a needle localization, a needle marking, or also a biopsy can be carried out with a high degree of precision. RF antennas are also allocated to the compression plates for the reception of the nuclear magnetic resonance signal.
Since in general the imaging region of the diagnostic apparatus is already filled by the patient, only a limited space is available for the adjustment of a conventional medical targeting apparatus at the patient. Particularly with magnetic resonance apparatuses, little space is available for manipulations at the targeting apparatus.
Another problem is that the adjustment of the targeting apparatus relative to the target region takes place directly at the patient. The examination time is prolonged due to the adjustment time and the preparation time, which results in a considerable burden for the patient.